Computerized cognitive training (CCT) is a promising new treatment option for depression. Isolating the mechanism of action of CCT, however, has remained elusive. First, critics have argued that CCT merely teaches to the test by providing practice on games similar to neuropsychological outcomes. Second, CCT research has relied primarily on waitlist and inactive control conditions. Depression affects 12% of adults aged 18-29, representing the highest age population at risk for depression. Ninety young adults with mild to moderate depression will take part in an 8-week, mobile phone-based CCT trial. Participants will be randomized to either processing speed/executive function (PS/EF) CCT, verbal ability CCT, or waitlist control. Participants in the PS/EF and verbal ability CCT groups will use the same mobile platform to complete a minimum of forty, 15-minute sessions over 8 weeks, while participants in the waitlist control will not receive CCT. Clinical assessments will be completed weekly and a comprehensive neuropsychological battery will be administered at baseline, week 4, and week 8. All participants will complete fMRI at baseline and then will be randomized to complete follow-up fMRI at week 4 or week 8. A comprehensive clinical and neuropsychological assessment will be completed 3 months after study completion to test for retention of treatment gains. This study proposes to determine whether PS/EF CCT is superior to, and leads to faster improvement than, verbal ability CCT and waitlist control (Aim 1) and whether PS/EF CCT leads to greater change in cognitive control network (CCN) activation (task-based) and connectivity (resting state) than verbal ability CCT and waitlist control (Aim 2). If the study goals are achieved it will have major implications for improving quality of life and reducing disability and healthcare costs in the age demographic with the highest rate of depression. This proposal is well positioned to meet the goals of the AREA program. It is based on previous research conducted in Dr. Sneed's Brain Performance Lab by graduate and undergraduate students in the Department of Psychology at Queens College of the City University of New York, which is a vitally important vehicle for the upward mobility of the urban disadvantaged. This research program provides a unique opportunity for undergraduate and graduate students to participate in cutting edge clinical research using neuroimaging and neuropsychological methodologies and critically supports an increase in the diversity of students preparing for careers in the biomedical and behavioral sciences.